Peter G. Sutton

Flash storage integration in the IBM System z EC12 I/O drawer

Flash storage is integrated for the first time on System z® as a card in the EC12 I/O drawer. This provides a number of functions and benefits in the immediate product, in addition to laying a foundation for further system benefits in future generations of System z systems. Enabling flash MLC (multilevel cell) technology as SCM (storage class memory) in an enterprise-class product required myriad diverse individual technological advances, together with a series of system design features. Extreme care and attention were paid to ensure that the required level of System z reliability was maintained. As with legacy I/O, the programming interface is subchannel-based. The subchannel programming interface is expanded with new architecture via the extended asynchronous-data-move facility. Operating system changes were required to enable exploitation of the features that this new system technology offers. These individual hardware, firmware, and software design aspects are described in this paper, along with the overall functionality and system-level value of this new technology.

IBM system z10 support for large pages

The IBM System z10™ mainframe provides an architectural framework for 1-MB virtual pages. With the new support provided in z/OS® 1.9, these large pages can be transparently used by middleware and applications. The use of large virtual memory pages for storage allocated at addresses above 2 GB can deliver significant performance gains. This paper reviews computer architecture trends and describes various implementations of large pages across the industry to explain why large pages are needed in todays operating system environments. It also reports results from innovative work focused on which workloads are subject to the largest performance boost from the use of large pages and how large-page support has been implemented on the System z10 platform and in the z/OS operating system. Results from recent performance tests are presented and analyzed.

Integrated high-performance data compression in the IBM z13

The IBM zEnterprise® Data Compression (zEDC) feature provides integrated high-performance data compression to the IBM z13™ and zEnterprise EC12 and BC12 processors. zEDC is a combined hardware feature (zEDC Express) and z/OS® software solution that provides high-performance, industry-standard-compliant compression and decompression. The zEDC Express device and the z/OS device support have been designed to provide compatibility with the zlib open source library for both compression and decompression. The base z/OS operating system and z/OS middleware significantly exploit the zEDC technology to provide access to this compression technology across a wide range of applications. This paper provides an overview of the zEDC Express hardware feature, the different z/OS device driver interfaces for using zEDC, including zlib, and discusses how this support was integrated into different aspects of the z/OS software stack.